(±)14-HDHA is an autoxidation product of DHA in vitro.{7479,7491} It is also produced from incubations of DHA in rat liver, brain, and intestinal microsomes.{7480,7490,7492} DHA is metabolized to 14(S)-HDHA by human platelets along with 11(S)-HDHA.{7483,7484,7492} 14(S)-HDHA is also produced by salmon gills upon stimulation with calcium ionophore.{7514} 14(S)-HDHA is an inhibitor of U-46619-induced human platelet aggregation and rabbit and rat aortic smooth muscle contraction with IC50 values of about 70, 3.6, and 5.3 μM, respectively.{7484,7481} (±)14-HDHA is a potential marker of oxidative stress in brain and retina where DHA is an abundant PUFA.